See a list of possible causes in order from the most common to the least.

Beriberi is caused by a vitamin B-1 (thiamine) deficiency. It's rare in areas that have access to nutritious food sources, but some diseases (ex. liver disease) and conditions (ex. prolonged diarrhea) can lead to it.

This condition is considered a medical emergency. Urgent care may be required.

Stingrays have venomous spines on their tails that can cause a painful wound, nausea, and weakness, and sometimes death. Swimming or snorkeling in shallow waters puts you at risk for coming in contact.

A venomous snake bite can be deadly and is a medical emergency. Even a bite from a harmless snake can cause infection or an allergic reaction, producing symptoms like pain and swelling, convulsions, nausea, or paralysis.

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